In the latter part of the 21st century, Singapore could face hotter and wetter days, if no global action is taken to curb greenhouse gas emissions. In a worst-case scenario, daily temperatures could spike to 32°C, while sea levels could rise by more than a metre.
This is according to findings from the first phase of the Second National Climate Change Study, which was released by the Meteorological Service Singapore’s (MSS) Centre for Climate Research Singapore on Wednesday (Apr 15).
The study made use of models from the Inter-governmental Panel on Climate Change (IPCC) 5th Assessment Report and scaled it down for it to be relevant to Singapore. It used a baseline period of 1980 to 2009 and projected it on the period between 2070 and 2099.
Daily temperatures, for example, could increase from the baseline average of 27.4°C to as much as 32°C – or a 4.6°C rise – should there be no concerted effort to tackle the greenhouse gas emission issue, according to the report.
The study also showed that the hot weather commonly experienced here between February and May could be exacerbated.
In the historical baseline period, there were about 25 days when temperatures hit or exceeded 34.1°C. In a less aggressive projection, Singapore could see between 74 and 108 days with such temperatures, but the worst-case scenario would see such temperatures become the norm here, the study found. Higher temperatures, coupled with the humidity, could result in more heat stress incidents for those working outdoors.
Singapore could also see more rainfall during the wet months of November to January. The percentage of contribution to annual rainfall from very wet days for the less aggressive projection is between 21 per cent and 35.3 per cent, while the other scenario would see a contribution of between 21.5 per cent to 44.1 per cent, the study found.
Meanwhile, the dry Southwest monsoon season could see between 12 and 30 per cent decrease in rainfall under the two scenarios.
February 2014 was the driest month for Singapore in 145 years, with little rain and parched weather conditions. Going forward, while experts said Singapore will not experience this on a yearly basis, such conditions may become more frequent.
Experts point out that rainfall patterns can also be affected by naturally occurring weather cycles.
“Not many people would doubt that some part of the temperature change we have seen for Singapore is due to climate change. But for rainfall, it is a tricky question to say how much of this can be attributed to climate change. It wouldn’t ever be saying it is due to climate change. It would be more of a question of a certain amount of that trend could be due to climate change.”
The findings will go towards the study’s second phase, which will examine the impact of climate change on infrastructure and water resources.
The study was commissioned by the National Environment Agency (NEA) together with the Met Office Hadley Centre in the UK. MSS said the second phase of the study is expected to be ready by the end of the year.